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JW April 9, 2006 23:40

To define Moist Air in Fluent

In Fluent, I want to change material to Moist air for HVAC CFD modelling. Could any one let me know the steps to change material to moist air in Fluent? (In the Fluent Material data base, there is no mixture for moist air. Only Air and Water Vapour is available).

Also please let me know how to introduce Relative Humidity for the Fluid mixture and to view the out put Relative humidity of a Moist air (Passing through a Heat exchanger).



Rags April 10, 2006 07:55

Re: To define Moist Air in Fluent
Probably you might have to use FIDAP for it as it is tailor-made for HVAC problems. I believe that u will have to include multiphase flow to include moist air in the simulation.

Ugur April 20, 2006 10:59

Re: To define Moist Air in Fluent
I think you've meant AIRPAK rather than FIDAP. In addition, if there is no condensation there is no need for multi-phase flow.

You could model this by taking your fluid as a mixture of air and water vapor, however Fluent does not use RH directly, you need to convert RH to mass fractions.

denise October 25, 2009 11:25

Hi Ugur and JW
i am trying to solve humidity transfer in enclosure, every where isolated except for ceiling..ceiling is cooled..but in Fluent i can see temperature gradient but there is no mass fraction of H2O gradient..i am trying to write UDF but, what is the source term? there is no generation of humidity in my to include natural convection using bossinique model in simple species transport without reaction phenomenon.?

yigitktu October 26, 2010 07:48

relative humidity
Hi ugur

I want to model relative humidity in fluent too. How can ı give mass fraction? And which model should ı use for this?

denise October 26, 2010 10:10

Yigit selam,
Ugurdan cevap alamadım ben de.
istersen sorunu açıkça Türkçe yaz sana cvp vermeye çalışırım

yigitktu October 26, 2010 16:43

define moist
Denis Merhaba,

İlgine teşekkür ederim. Fluentte hava için girişte bağıl nem tanımlamak istiyorum. Hangi model daha uygun bilmiyorum. Yardımcı olabilirsen sevinirim.

sandeeprapol April 29, 2015 05:18

how to add RH to air Fluent
Hi JW,

Can you help me how to add RH to air in Ansys Fluent step by step.

Sandeep Rapol

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